Abstract：
Primary ectopic extradural and extraspinal meningiomas are rare. We present a unique case of this type of meningioma in the brachial plexus. A 25-year-old man consulted us because of neuropathic supraclavicular pain and the appearance of a supraclavicular mass whose volume had increased. Clinical examination found paresis of the deltoid, biceps brachii and brachialis muscles rated as M4 (MRC) and a strong Tinel sign at the supraclavicular fossa, over the palpable mass. There was no sign pointing towards central nervous system involvement or altered general condition. MRI revealed a mass measuring 53 × 24 mm invading the C5-C6 plexus roots and the primary upper trunk, but not the bone or spinal area. This lesion was hyperintense on DWI/ADC, hyperintense on T2 with hypointense spots, and hypointense on T1 with intense heterogeneous gadolinium enhancement. Excisional biopsy was done 6 months after symptoms started. The tumor had developed at the C5 root, which was fibrous and at the C6 root, which was grossly normal. Anatomical pathology confirmed the WHO grade 1 meningioma, meningothelial and psammomatous histological subtypes. At 6 months, a follow-up MRI found no postoperative tumor remnants or recurrence. During the postoperative course, persistent paralysis of the deltoid muscle at 5 months justified a nerve transfer. This is a rare case of ectopic extraspinal and extradural meningioma of the brachial plexus. The diagnosis of an ectopic meningioma must be considered when a patient presents with a brachial plexus tumor causing neurological deficits. The extradural nature is not sufficient to rule out this diagnosis.
摘要：
原发性异位硬膜外和脊柱外脑膜瘤很少见。我们介绍了臂丛神经中这种类型脑膜瘤的独特病例。一名25岁的男子因神经性锁骨上疼痛和锁骨上肿块的出现而向我们咨询。临床检查发现三角肌轻瘫，肱二头肌和肱肌评分为M4（MRC），锁骨上窝有强烈的Tinel征，明显的肿块。没有迹象表明中枢神经系统受累或一般状况改变。MRI显示一个53×24毫米的肿块侵入C5-C6丛根和主要上干，但不是骨头或脊柱区域.该病变在DWI/ADC上表现为高强度，T2上有高强度点，在T1上呈低信号，具有强烈的异质钆增强。症状开始后6个月进行切除活检。肿瘤在C5根部发展，它是纤维状的，在C6根部，这很正常.解剖病理证实WHO1级脑膜瘤，脑膜上皮和子宫内膜组织学亚型。6个月时,随访MRI未发现术后肿瘤残留或复发.在术后过程中，在5个月时，三角肌的持续瘫痪证明了神经转移的合理性。这是一例罕见的臂丛神经的脊柱外和硬膜外脑膜瘤。当患者出现臂丛肿瘤导致神经功能缺损时，必须考虑异位脑膜瘤的诊断。硬膜外的性质不足以排除这种诊断。
